Various types of photoacoustic sensors are known to detect gases. These include, Fritz et al., US Patent Application No. 2009/0320561, published Dec. 31, 2009 and entitled “Photoacoustic Cell”; Fritz et al., US Patent Application No. 2010/0027012, published Feb. 4, 2010 and entitled, “Photoacoustic Spectroscopy System”; Fritz et al., US Patent Application No. 2010/0045998, published Feb. 25, 2010 and entitled “Photoacoustic Sensor”; and Tobias, US Patent Application No. 2010/0147051, published Jun. 17, 2010 and entitled, “Apparatus and Method for Using the Speed of Sound in Photoacoustic Gas Sensor Measurements. The above noted published applications have been assigned to the assignee hereof, and are incorporated herein by reference.
Precise signal acquisition is important for accurate gas concentration measurement using photoacoustic sensors. A high level of signal to noise ratio must be obtained from a primary light source and pressure measurement system in order to acquire a photoacoustic signal and have sufficient differentiation between the actual photoacoustic signal and background effects.